Micrometer-calipers.



No. 676,637. Patented lune l8, l90l. F. SPALDING.

MIOBOMETER CALIPEBS.

(Application filed m. 9, 1900.

(No Model.)

wr rxzssrg: 2564.7?

UNITED STATES FRANK SPALDING, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO BROWN &

PATENT OFFICE.

SHARPE MANUFACTURING COMPANY, OF SAME PLACE.

MlCROMETER-CALIPERS.

SPECIFICATION forming part of Letters Patent No. 676,637, dated June 1901- Application filed February 9, 1900. Serial No. 4,656. (No model.)

To all whom/it may concern.-

Be it known that I, FRANK SPALDING, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented a new and useful Improvement in Micrometer-Oalipers, of which the following is a specification.

The invention relates to an improvement in instruments used for measuring sheet metal, wire, and other articles by calipering; and it consists in the peculiar and novel construction whereby micrometric measurement is secured, as will be more fully set forth hereinafter.

The object of this invention is to facilitate the reading of micrometer-calipers adapted to measure the thickness of sheet metal or other articles.

Figure 1 is a side view of my improved micrometer calipers. Fig. 2 is an end view of the same. Fig. 3 is a sectional view of the calipers, showing the dial supported on the spindle and held against rotation with the spindle. Fig. 4: is a sectional view of part of the frame and an adjacent part of the dial, showing the preferred means for holding the dial against rotation. Fig. 5 is a sectional view of part of the dial and the adjacent part of the frame, showing a modified form of connection between the two.

In the drawings, a indicates the frame of the calipers, having the usual U -shaped opening, on one side of which the arm a supports the anvil a? and on the other side of which the: arm a supports the internally screwthreaded barrel a with which the screwthreaded spindle b is in screw-thread en gagement.

The frame a is provided with the handhold a having the hole a. and the arm a, along the 11 per margin of which the graduated index 0. indicates decimal fractions of a standard of measurement. The barrel 0L may be graduated to correspond with the index a The spindle b, which is in screw-thread engagement with the internally-screw-threaded portion of the barrel a, has rigidly secured to it the sleeve b, the cylindrical portion of which is knurled to facilitate the rotation of the sleeve. The collar b loosely fits the ey lindrical portion 19 of the spindle. The dial '1) is mounted on the collar 71 and held between the end of the sleeve b and the nut 12 in screw-thread engagement with the spindle Z).

The pointer b is secured to the end of the spindle b by the screw 1) and rotates with the same.

The dial 5 is held against rotation by connecting the same with the Way 19 on the arm a of the frame in any manner by which the dial is free to move longitudinally with the spindle 1) without rotating the same.

In the manner shown in Figs. 3 and 4 a spring-pressed post inserted into a hole in the peripheral portion of the dial enters with its pointed end a \l-shaped groove in the way 12 and, as shown in Fig. 5, a spline on the way If enters a groove in the periphery of the dial. This spline may be V-shaped, as shown in solid lines, or have parallel sides, as is indi- 7o cated in broken lines in Fig. 5.

The head of the screw a", secured in the end of the arm a formsa stop by which the outward movement of the dial b is limited.

In the drawings the calipers are shown as indicating a measurement of 0ne-tenth of an inch or other unit of measurement. The end of the sleeve 7) is at l of the index on the barrel a and the forward edge of the dial is at 1 of the index on the arm a of the frame a.

The spaces between the lines of the indexes marked by numerals are divided by shorter lines into four spaces, each indicating onefourth of the distance between the lines in dicated by numerals. on the spindle b is such that at each complete revolution of the spindle the sleeve and the may be easily read on the dial, which is of 95 comparatively large diameter.

In use when measuring plates the dial is in full view, so that thousandths may easily be read.

Having thus described my invention, I 100 claim as new and desire to secure by Letters Patent 1. In micrometer-calipers, a dial supported on and moving longitudinally with the spin- The pitch of the screw The dle, means for holding the dial against rotation with the spindle, and a pointer secured to and rotating with the spindle and indicating on the flat face of the dial, as described.

2. In micrometer-calipers, in combination, a frame, an internally-screw-threaded barrel, and a graduated index on the frame, a spindle in screw-thread engagement with the barrel, a sleeve secured to and rotating with the spindle, a dial journaled on and carried longitudinally with the spindle, means for holding the dial against rotation, and a pointer secured to and turning with the spindle, whereby the rotation of the spindle is indicated on the dial, as described.

3. In micrometer-calipers, the combination with the frame a provided, with the barrel a and the arm a the spindle bin screw-thread engagement with the barrel a and the sleeve b secured to and rotating with the. spindle, of the collar 11 on the unthreaded portion of the spindle, the dial b rotatably mounted on the collar, the nut b in screw-thread engagement with the spindle, the pointer 19 secured to and rotating with the spindle, and a connection between the dial and the arm a? on the frame, whereby the dial is moved longitudinally with the spindle and the rotation of the spindle is indicated on the dial, as described.

4. In micrometer-calipers, a non-rotatable dial supported on and moving longitudinally with the spindle and a pointer secured to and rotating with the spindle and indicating on the flat face of the dial, as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FRANK SPALDING. Vitnesses:

J. A. MILLER, J r., B. M. SIMMS. 

